Because the buffers are `MaybeUninit<V8Slice<u8>`, and the owner of the
`BoundedBufferChannel` is not obligated to read each and every bit of
data, we may find that some buffers were not automatically dropped if
unread by the time the `BoundedBufferChannelInner` is dropped.
Possible repro:
```
Deno.serve(() => new Response(new ReadableStream({ start(controller) { controller.enqueue(new Uint8Array(100_000_000)) } })));
```
```bash
while true; do curl localhost:8000 | dd count=1; done
```
625d09937a